[amsat-bb] Re: metal or non metal cross booms

[Prathap Kumar]

Hi
I got the thick wall Blue PVC pipes used for plumbing wrapped in fibreglass 
mat and its been in use for over ten years now.
The final OD is now about 40mm.
It does support both my cross yagis on the rotator.
I am also looking for the fibreglass tube with thick wall and hope to get 
some here in Bangalore and will keep you informed Gopal.
Best 73
Pop
VU2POP



> Gopal,
>
> A good decision that you made.  A study by Kent, WA5VJB, shows that
> only some sensitivity of position between elements on the antenna
> boom impacts using a metal crossboom if the antenna is mounted in the
> "X" confinguration.  My satellite antennas are mounted this way.
>
> 73 Ed - KL7UW
>
> At 05:50 PM 4/5/2008, Gopal Madhavan wrote:
>>I have experimented with both non-metallic and metallic cross booms after
>>reading numerous articles on the subject some years ago. With CP antennae
>>mounted in X configuration there seems to be hardly any difference in
>>performance. I speak of experiments done when AO-40 was active.
>>
>>I now use a metallic boom as it gives very good rigidity to mount two CP
>>antennae, a small dish for 2.4 GHz, preamps etc. Here in India I do not 
>>have
>>the option to order a good section of fibre glass cross boom any way, and 
>>so
>>had made do with PVC tube wrapped in fibre glass, but it eventually sagged
>>and I had to periodically rotate it 180 degrees to keep it somewhat level.
>>
>>Gopal VU2GMN
>>
>>
>>_______________________________________________
>>Sent via AMSAT-BB at amsat.org. Opinions expressed are those of the author.
>>Not an AMSAT-NA member? Join now to support the amateur satellite program!
>>Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
>
> _______________________________________________
> Sent via AMSAT-BB at amsat.org. Opinions expressed are those of the author.
> Not an AMSAT-NA member? Join now to support the amateur satellite program!
> Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb